Are characters made up of pixels?

Question

On a computer screen, are the characters made up of pixels? If so, it means that characters are images!

And if the characters are made up of pixels, then why are there ASCII, UNICODE and other standards that associate binary digits to different character formats, but there are no standards that associate image formats with binary digits? Because if both are made up of pixels (characters and images), what is the difference between them?

Answer 1

On a computer screen, are the characters made up of pixels? if so, it means that characters are images!

On a typical modern screen, yes the graphical representation of a character is a group of pixels. No, computers don't always have a screen

For example in the past people used to interact with computers via multiple types of terminals like a mechanical terminal where the texts are printed directly to paper. Or sometimes a vector screen or a 16-segment/14-segment display is also used where the text representation has no pixel at all. Many computers don't even have a screen or a way to display characters and interact with humans via switches, LEDs, punched cards, network or serial port...

So the premise of the question is already wrong. Characters has nothing to do with pixels. Even when displaying characters on the screen then the pixels representing a character also vary depending on the font face and font size

Character traditionally means a symbol or a glyph representing something. In computing character means a unit of information that roughly corresponds to a grapheme, grapheme-like unit, or symbol, such as in an alphabet or syllabary in the written form of a natural language. None of them says anything about pixels

Each language has a known set of symbols, so logically they're grouped together and each assigned a number. The whole set of those numbers and their mappings is called a character set. You can see that it makes sense to associate numbers with characters but doing the same for images make no sense. What are the common thing in images that we can map?

In the past there were no need to cooperate with people using other languages so each group of people chose a small set that works for their own language. However with the advent of portable devices and the internet, that doesn't work anymore. It'll be extremely awkward to receive a message that you can't read, or send an email that the customer sees as a bunch of garbage. That's why a bigger character set called Unicode was invented

However character set is just a way to map numbers to glyphs in computers. To deal with characters we also need a way to encode those numbers which is called character encoding. For example in a variable length encoding a long number may be encoded using more bytes. Unicode has multiple encodings like UTF-1, UTF-7, UTF-8, UTF-16 or UTF-32

See What's the difference between a character, a code point, a glyph and a grapheme?

Answer 2

No, #1: Characters are not "on a computer screen". What goes on the screen is the result of all kinds of rendering and painting and combining onto a 2-D grid of pixels.

No, #2: Unicode characters are independent of the specific fonts used to present them graphically. So, with one font, a character will end up producing certain pixels, and with another font - other pixels altogether.

No, #3: Character strings are held in your computer's memory as sequences of bytes, i.e. numeric values (with each character typically occupying one byte, or two, or a variable number of bytes).